docs: def create_db(self, models):
          """Creates the in-memory SQLite database from the model
          configuration."""
          # first create the table definitions
          self.tables = dict(
              [
                  (model_name, self.create_model_table(model))
                  for model_name, model in iteritems(models)
              ]
          )
          # now create the tables in memory
          logger.debug("Creating %d database table(s)...", len(self.tables))
          try:
              self.Base.metadata.create_all(self.engine)
          except Exception as exc:
              raise StatikError(
                  message="Failed to create in-memory data model.",
                  orig_exc=exc
              )
          self.load_all_model_data(models)